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I know Marlin did do a half and half model for someone, but can't remember any more than that.
Not sure if there is more than one? Gerry Haines in Weymouth has a Cabrio with a Sportster front end (Ford Cortina) which I think works really well. Had I known Marlin were prepared to do it, I would have chosen the Cabrio, with the BMW Sportster front end.
It is interesting to note Gerry is not happy with his brakes either!! He has converted his front end from Cortina to Sierra hubs (with 4 pots?). Connoisseurs may spot the changes here?
In fact it looks more like a 3/4 - 1/4 cause the bonnet and nosecone is definitely still Cabrio. The Sportster doesn't have the distinct V in the bonnet top. It could be why it looks a bit odd to me - I am used to the Sporster shaped bonnet having looked at it for the last 5 years whilst building!
That certainly does look like a 4 pot ali calliper - any feed back on what he thinks of the 4 pot brakes?
Patrick
Gerry is quote, "happier" with the brakes.
Reading between the lines I think it comes back to a lack of servo boost.
First one to solve this problem will have several followers.........
Mike
Have been thinking about the brakes,..have seen bigger brake kit for the e30 hubs on rally design website,wilwood calipers and bigger dics, from approx £380-450 depending on spec, any views?
Not sure if there is more than one? Gerry Haines in Weymouth has a Cabrio with a Sportster front end (Ford Cortina) which I think works really well. Had I known Marlin were prepared to do it, I would have chosen the Cabrio, with the BMW Sportster front end.
It is interesting to note Gerry is not happy with his brakes either!! He has converted his front end from Cortina to Sierra hubs (with 4 pots?). Connoisseurs may spot the changes here?
Have been thinking about the brakes,..have seen bigger brake kit for the e30 hubs on rally design website,wilwood calipers and bigger dics, from approx £380-450 depending on spec, any views?
I think you will still need to exert a lot of pressure relative to the feel of a modern car (- possibly even more if you increase the surface area of the pots?). Patrick has considered 4 pots, yet says he can still lock his brakes. I don't think it is about brake friction, but more about pedal effort.
Has anyone considered altering the relative positions of the pedal holes to reduce the distance from fulcrum to master cylinder, by say 10mm, and lengthening the pedal by the same. This would significantly reduce the pedal effort, but of course will result in more pedal travel. And it will be by far the cheapest solution.
Mike
This is really interesting.
I do not think it would be too difficult to modify the pedal box to raise the brake pedal pivot point by 10mm, and then make a new pedal to the new dimensions to test it.Interesting.
Mike
Note the comment under:
Brake Lines and Fluid
Long runs should be done with hard tubing to avoid expansion of flexible line. The amount of flexible braided hose in the system should be kept to a minimum
Could you get this calculator to work?
I've tried and can not enter figures.
The master cylinder on a sierra is a 22mm bore (7/8" in US terms)
My pedal is split 75mm/310mm so approx 4:1
But can not get the calculator to tell me anything?!!
Mike
Hitting submit with the default figures (150lbs on the foot pedal, desired system pressure of 1200), the 7/8" master cylinder line gives a force on the master rod of 720lbs, and the foot leaver ratio is 4.8:1
in the bottom box 'custom' enter the area of the mater cylinder in square inches (22mm = 0.6 sq in).
Enter the desired system pressur (PSI in the next box along)
In the top boxes 'hand lever force' and 'foot lever force' enter the numbers you want, or leave then at the default.
Click submit.
It then calculates the two ratios you need.
To get the foot pedal raio to 4:1 you have to specify a pedal force of 180 lbs.
HOWEVER these calculations ignore the effect of a servo!
eep: